Pharmaceutical compositions containing substituted phenyl sulphoxides and sulphones and method of using same

ABSTRACT

The invention relates to a method of producing peripheral vasodilation which comprise the oral or parenteral administration in unit dosage form of a compound having the formula   WHERE N IS 1 OR 2, P IS 1 OR 2, R, R1 and R2 represent specified radicals. The above compounds are preferably administered together with a pharmaceutically acceptable diluent or carrier therefor, in the form of a pharmaceutical composition.

United States Patent [1 1 [4 1 May 27, 1975 Bentley et al.

[ PHARMACEUTICAL COMPOSITIONS CONTAINING SUBSTITUTED PHENYL SULPHOXIDES AND SULPIIONES AND METHOD OF USING SAME [75] Inventors: Kenneth Walter Bentley, Willerby; William Ian Rushworth, Beverley, both of England [73] Assignee: Reckitt & Colman Products Limited,

Hull, Yorkshire, England [22] Filed: Nov. 6, 1973 [21] Appl. No.: 413,229

Related U.S. Application Data '[62] Division of Ser. No. 20l,563, Nov. 2l, l97l, Pat. No.

[30] Foreign Application Priority Data FOREIGN PATENTS OR APPLICATIONS 875,533 8/1961 United Kingdom 1,042,489 9/1966 United Kingdom OTHER PUBLICATIONS Burton and Hog, Auth., J. Chem. Soc., No. 5, I945. Baliait, .lour. Indian Chemical Soc., Vol. 38, No. l 1961.

Primary Examiner.lerome D. Goldberg Attorney, Agent, or FirmBacon. & Thomas [57] ABSTRACT The invention relates to a method of producing peripheral vasodilation which comprise the oral or parenteral administration in unit dosage form of a compound having the formula where n is l or 2, p is l or 2, R, R and R represent specified radicals. The above compounds are preferably administered together with a pharmaceutically acceptable diluent or carrier therefor, in the form of a pharmaceutical composition.

10 Claims, No Drawings PHARMACEUTICAL COMPOSITIONS CONTAINING SUBSTITUTED PI-IENYL SULPHOXIDES AND SULPHONES AND METHOD OF USING SAME This is a division of application Ser. No. 201,563 filed Nov. 21, 1971 now U.S. Pat. No. 3,804,904.

This invention relates to pharmaceutical compositions and in particular to pharmaceutical compositions which may be used in the treatment of disorders of the cardiovascular system.

According to this invention there are provided pharmaceutical compositions comprising a compound of the formula:

in which n is an integer l or 2,

p is an integer l or 2 when n l R represents an alkoxy or alkyl group having 1 to 3 carbon atoms,

when n 2, (R),, represents alkoxy or alkyl groups having l to 3 carbon atoms, chlorine atoms or when attached to adjacent carbon atoms of the benzene ring the group -O(CH ),,,O where m is an integer 1, 2 or 3,

R represents a hydrogen atom or when (R),, represents at least one alkoxy group R may also represent a chlorine atom, a bromine atom, an alkoxy or alkyl group having 1 to 3 carbon atoms, a nitro group, an amino group or a pharmaceutically acceptable salt of an amino group,

R represents an alkyl group having 1 to 7 carbon atoms, an alkenyl or alkynyl group having 3 to carbon atoms or a hydroxyalkyl group having 2 or 3 carbon atoms; together with one or more pharmaceutically acceptable diluents or carriers.

ln particular the present invention provides pharmaceutical compositions comprising sulphoxides of the formula in which R, R, R and n are as hereinbefore defined together with one or more pharmaceutically acceptable diluents or carriers.

In particular the present invention provides pharmaceutical compositions comprising sulphones of the formula in which R, R, R and n are as hereinbefore defined together with one or more pharmaceutically acceptable diluents or carriers.

The invention also includes compounds of the formula u s --n in which R represents a hydrogen atom or a methoxy group, and R represents an alkyl group having 1 to 7 carbon atoms, an alkenyl or alkynyl group having 3 to 5 carbon atoms, or a hydroxyalkyl group having 2 or 3 carbon atoms.

These compositions produce a significant reduction in blood pressure when administered to normotensive, DOCA or renal rats and also cats and dogs and have utility in the treatment of those conditions in man for which an anti-hypertensive or vasodilator drug is employed.

The pharmaceutical compositions may be in a form suitable for oral administration or in a form suitable for parenteral administration. Compositions intended for oral use may be in the form of tablets, packaged powder or granules, aqueous or oily suspensions, emulsions, hard or soft capsules, lozenges or syrups. Compositions intended for oral use may be prepared according to any method known to the art for the manufacture of pharmaceutical compositions and such compositions may contain one or more sweetening, flavouring, colouring or preserving agents in order to provide pharmaceutically elegant and palatable preparations.

Tablets contain the compound of said formula in admixture with excipients which are suitable for manufacture of tablets. These excipients may be inert diluents, such as, calcium phosphate, lactose, sucrose or dextrose; granulating and disintegrating agents, such as starch or alginic acid; binding agents such as starch, gelatine or acacia; and lubricating agents such as magnesium stearate, stearic acid or talc.

Compositions for oral use in the form of hard gelatine capsules contain the compound of said formula mixed with an inert solid diluent such as calcium phosphate, lactose or kaolin, or as soft gelatine capsules in which the compound of said formula is mixed with an oily medium such as arachis oil, liquid paraffin or olive oil.

Compositions intended for parenteral administration may be in the form of sterile injectable preparations such as solutions or suspensions in water, saline or [,3- butane diol. The preparations may also contain suitable wetting agents and suspending agents.

For the purposes of convenience and accuracy of dosing the compositions are advantageously employed in a unit dosage form. For oral administration the unit dosage form contains from 11mg to 500mg, preferable from 10mg to mg, of the compound of said formula. Parenteral unit dosage forms contain from 1mg to 10 mg of the compound of said formula per lml of the preparation. The compounds. of said formula may be prepared by oxidising the corresponding thioethers. The oxidiation may be carried out employing as the oxidising agent hydrogen peroxide, N-halosucciniaides,

l-chlorobenzo-triazole and other known chemical equivalents.

1n the preparation of compounds of said formula in which p 1 (sulphoxides) suitable methods for carrying out this oxidation include the use of hydrogen peroxide in acetic acid, N-bromosuccinimide or N- chlorosuccinimide in methanol, and lchlorobenzotriazole in methanol or methylenechloride.

EXAMPLE 2 3,4-Dimethoxyphenylethyl sulphoxide 3,4-Dimethoxythiophenol (8.6g, 0.05 mole). sodium (l.l5g., 0.05 mole), ethanol (50ml) and ethyl iodide (7.8g, 0.05 mole) were reacted according to the manner of Example 1 to give 3,4-dimethoxyphenylethyl sulphide (7.3g) b.p. 100-l08C/0.2 mm.

Anal.

with an organo-halide or sulphate.

The following examples illustrate the preparation of compounds of said formula:

EXAMPLE 1 3,4-Dimethoxyphenylmethyl sulphoxide 3,4-Dimethoxythiophenol (28.3g, 0.17 mole; A.A. Levi and S. Smiles. J. Chem. Soc. 520 (1931)) was added to sodium (3.83g., 0.17 mole) in absolute ethanol. Dimethyl sulphate (20.8g., 0.17 mole) was slowly added to the mixture which was then refluxed for 2 hours. The solvent was removed under pressure. The residue was extracted with chloroform. The extracts were washed with water, dried over magnesium sulphate and evaporated to give 3,4-dimethoxyphenyl- 4O methyl sulphide (286g) b.p. ll0C/0.8 mm.

C H O S requires Found:

The 3,4-dimethoxyphenylethyl sulphide (1.98g) was oxidised, according to the manner of Example 1, to give 3,4-dimethoxyphenylethyl sulphoxide (1.6g).

Anal. Calcd. for C H O s C,56.1 H.6.6

Found: C,56.0 H,6.4%

EXAMPLE 3 3,4-Dichlorophenylmethyl sulphoxide a. 3,4-Dichlorothiophenol (8.9g, 0.05 mole; S.M. Dandin et a1 Chem. Abs. 52, 8071), sodium (l.l5g., 0.05 mole), ethanol m1) and methyl iodide (7.1g, 0.05 mole) were reacted according to the manner of Example 1 to give 3,4-dichlorophenylmethyl sulphide (7.2g) b.p. 76-80C/0. 2 mm.

The 3,4-dichlorophenylmethyl sulphide (5.7g, 0.03 mole) was dissolved in dry methanol (80ml) and cooled to 0C in an ice-bath. N-chlorosuccinimide (4g, 0.03 mole) was added in increments whilst keeping the temperature below 10C. The mixture was allowed to Calcd. for C H, O S Found: C,58.5

Anal.

30 percent Hydrogen peroxide (11.3m1., 0.1 mole) was added to the 3,4-dimethoxyphenylmethyl sulphide (18.4g, 0.1 mole) in glacial acetic acid (ml) with cooling. The mixture after remaining at room tempera- 50 ture for 24 hours was made alkaline by the slow addition of ice-cold aqueous sodium hydroxide. The mixture was extracted with chloroform. The extracts were stand for an hour. The solvent was removed under reduced pressure. The residue was extracted with chloroform. The extracts were washed with water, dried over magnesium sulphate and evaporated to give a white oil, which on trituration with light petroleum ether afforded crystalline 3,4-dichlorophenylmethyl sulphoxide (4.8g) m.p. 7274C.

Anal. Calcd. for C H Cl OS Found: C,39.7

washed with water, dried over magnesium sulphate and evaporated to dryness under reduced pressure to give 60 white crystalline 3,4-dimethoxyphenylmethyl sulphoxide (15.1g). A sample recrystallised from diisopropyl ether had m.p. 82-84C.

H,2.7 Ch.34.2

b. The 3,4-dichlorophenylmethyl sulphide (4.0g, 0.03 mole) was dissolved in dry methylene chloride (50ml) and cooled to 78C in a dry-ice/alcohol bath. l-Chlorobenzotriazole (3.6g, 0.03 mole) was added and the mixture was allowed to warm to room tempera- C,54.l H,6.3

Anal.

Calcd. for C H O S Found: C,53.9

give a produce (3.5g) m.p. 7274C., identical to that 5 obtained in (a) above.

EXAMPLE 4 2,S-Dimethoxyphenylmethyl sulphoxide EXAMPLE 6 3,4-Dimethoxy-o-nitrophenylmethyl sulphone 3,4-Dimethoxyphenylmethyl sulphone (6.5g., 0.03 mole) was dissolved in concentrated nitric acid (20ml) and allowed to stand at room temperature for 1 hour. The mixture was poured onto ice and the yellow pre- 2,5 Dimeth0XythiOphen0] (2.8%, 00 7 mole; Suter cipitate filtered off and recrystallised from ethanol to and Hansen J. Am. Chem. Soc. 54, 4102, (1932)) was added to sodium (0.4g, 0.017 mole) in absolute ethagive 3,4-dimethoxy-6-nitro'phenylmethyl sulphone (5.8g) m.p. 186-l88C.

Anal. Calcd. for CQHHNOGS C,4l.4 H,4.2 N,5.4 S,12.3

Found: C,41.4 H,4.1 N.5.4 5,123

EXAMPLE 7 nol. Dimethyl sulphate (2.1g., 0.017 mole) was slowly added to the mixture which was then reflexed for 2 hours. The solvent was removed under reduced pressure. The residue was extracted with chloroform. The extracts were washed with water, dried over magnesium sulphate and evaporated to give 2,5-dimethoxphenylmethyl sulphide (2.8g) b.p. 9296C/0.3mm.

6-Amino-3,4dimethoxyphenylmethyl sulphone 3,4-Dimethoxy-6-nitrophenylmethyl sulphone (4.0g) was dissolved in acetic acid (100ml) and stannous chloride (20g) in concentrated hydrochloric acid (20ml) Anal. C alcd. for C H, O S

Found: C,59.0

The 2,S-dimethoxyphenylmethyl sulphide (2.3g) was oxidised according to the manner of Example 1 to give 2,5-dimethoxyphenylmethyl sulphoxide (1.8g) m.p. 7072C.

added. The mixture was heated on a water bath for one-half hour, the acetic acid was evaporated off under reduced pressure, and the aqueous layer was basified with dilute aqueous sodium hydroxide and extracted 3,4-Dimethoxypheny1methyl sulphone 3,4-Dimethoxyphenylmethyl sulphide (6.1g., 0.03 mole) and 30 percent hydrogen peroxide (1 1.3ml., 0.1 mole) were heated on a steam bath for 2 hours in glawith chloroform. The chloroform extracts were dried over magnesium sulphate and evaporated to give a yellow oil which solidified on standing. The product was recrystallised from ethanol to give 6-amino-3,4-

dimethoxyphenylmethyl sulphone (1.4g) m.p. 9798C.

Anal. Calcd. for C H NO S C,46.8 l-l,5.7 N,6.l S,13.9

Found: C,46.9 H56 N,6.2 3,131.8

cial acetic acid (ml). The mixture was poured on to 50 ice (300g) and the resulting white precipitate filtered, washed well with water and recrystallised from ethanol to give 3,4-dimethoxyphenylmethyl sulphone (5.7g) m.p. -117c.

The Table below sets out details of further examples of compounds of said formula. The compounds in which p 1 (sulphoxides) were prepared by the method of Example 1, and those in which p 2 (sulphones) were prepared by the method of Example 5.

Anal. Calcd. for C,,H, O S C,50.0 H,5.6 5,148

Found: C,49.8 H,5.8 S,14.7

Table Ex- Substituent on R P m.p Formula Calcd. Found ample Benzene Ring "C C H S C H S s MeO MeO n-Pr c u o s 57.9 7.1 4.1 57.7 7.0 13.6 9 McO McO i-Pr 1 68-70 c u o s 57.9 7.1 4.1 57.9 6.9 14.1 10 M00 M00 n-Bu l C H O S 59.5 7.5 59.5 7.6

11 MeO MeO i-Bu C H O S 59.5 7.5 58.9 7.4

12 MeO McO CH CH=CH 1 C H, O -,S 1 58.5 6.2 58.5 6.3

13 M00 McO CH CH OH 1 -6 G i-1, 0 5 52.2 6.1 13.9 51.8 6.1 13.8 14 MeO MeO MC 1 C H Q S 54.1 6.1 53.7 6.0

15 MeO McO n-Pr 1 C I-1, 0 8 57.9 7.1 57.9 7.3

16 M00 1 c.,11,.o.,s 57.9 7.1 57.7 6.9

Table-Continued Ex- Substituent on R P m.p Formula Calcd. Found ample Benzene Ring "C C H S C H S l7 McO MeO n-Bu l c H o s 59.5 7.5 13.3 59.3 7.2 12.8 18 MeO MeO i-Bu 1 12 O, 59.5 7.5 59.3 7.2

19 MeO MeO CH CH=CH 1 C H O S 58.5 6.2 58.8 6.3

20 MeO MeO Cl-l CH ol-l 1 108-110 C H O S 52.2 6.1 13.9 52.4 6.1 14.1 21 McO MeO N0 Me 1 C H NO S 44.1 4.5 13.1 44.1 4.5 13.2 22 MeO MeO MeO Me 1 74-6 C H O S 52.2 6.1 13.9 52.2 6.1 13.9 23 MeO MeO Br Me 1 152-3 C H BrO S 38.7 4.0 11.5 38.7 3.9 11.5 24 Me Me Me 1 C H, OS 64.3 7.2 19.1 63.9 7.1 19.3 25 EtO EtO Me 1 61-2 C H O S 57.9 7.1 12.1 57.6 6.9 14.0 26 OCH,.CH O Me 1 C H O S 54.6 5.1 16.2 53.8 5.0 16.1 27 MeO Me 1 43 C H O S 56.5 5.9 18.9 56.2 6.1 18.5 28 MeO Me 1 C H O S 56.5 5.9 18.9 56.4 5.8 18.6 29 MeO Me 1 C H O S 56.5 5.9 18.9 56.3 6.1 18.2 30 Me Me 1 C H OS 62.4 6.6 20.8 62.7 6.8 20.4 31 MeO MeO Me 1 C H O S 54.1 6.1 16.0 54.1 6.0 16.2 32 MeO MeO Me 1 97-8 C H O S 54.1 6.1 16.0 53.6 6.2 15.7 33 MeO MeO Me 1 74-6 C H O S 54.1 6.1 16.0 54.3 6.2 16.0 34 C1 MeO Me 1 54 C H CIO S 47.0 4.4 15.7 46.9 4.5 15.7 35 C1 C1 Me 1 84 C 1-1 C1 OS 40.4 2.9 15.4 40.2 3.0 15.5 36 C1 C1 Me I 76 C H C1 OS 40.4 2.9 15.4 40.4 2.9 15.2 37 C1 C1 Me 1 92-94 C H Cl OS 40.4 2.9 15.4 40.1 2.9 15.6 38 C1 C1 Me 1 69-71 C H CI OS 40.4 2.9 15.4 40.1 2.9 15.6 39 Cl Me Me 1 70-71 C H CIOS 51.1 4.5 17.1 51.0 4.5 17.0 40 Me MeO Me 1 53-55 C H O S 58.7 6.6 17.4 58.6 6.4 17.5 41 Et Et Me 1 C H OS 67.4 8.2 16.4 66.5 8.3 16.4 42 B0 B0 n-Pr 1 c nzno s 61.0 7.9 12.5 60.7 8.2 12.0 43 MeO MeO n-Am l a 20 61.0 7.9 12.5 60.6 8.0 12.0 44 MeO MeO n-C H 1 C, ,H ,,O S 63.4 8.5 11.3 63.4 8.5 11.4 45 MeO MeO Me Me 1 92-3 C, H,.,O -,S 56.1 6.6 15.0 56.0 6.5 14.9 46 MeO MeO MeO Me 1 117-9 C H O S 52.2 6.1 13.9 53.7 6.2 14.5 47 C1 C1 Et 1 C H CI OS 43.1 3.6 14.4 42.9 3.6 14.2 48 C1 C1 n-Bu 1 C H C1 OS 47.9 4.8 12.8 48.1 4.7 13.0 49 C1 C1 n-Pr 1 C H Cl OS 45.6 4.3 13.5 45.8 4.2 13.5 50 C1 C1 Et 1 CnHgClgOS 43.1 3.6 14.4 43.2 3.6 15.1 51 C1 C1 Et 1 C H Cl OS 43.1 3.6 14.4 42.6 3.6 14.7 52 C1 C1 n-Pr 1 C H C1 OS 45.6 4.3 13.5 45.6 4.2 13.8 53 C1 C1 n-Bu 1 CmHu lzOgS 47.9 4.8 12.8 47.6 4.8 13.2 54 C1 C1 n-Bu 1 C H Cl O S 47.9 4.8 12.8 47.9 4.9 12.9 55 C1 C1 n-Pr 1 C H CI OS 45.6 4.3 13.5 45.7 4.3 13.6 56 MeO MeO Me Me 2 141-142 C H O S 52.2 6.1 13.9 52.0 6.2 14.1 57 MeO MeO Br Me 2 179-80 C H BrO S 36.6 3.2 10.9 36.5 3.9 11.0 58 MeO MeO MeO Me 2 193-4 C H O S 48.8 5.7 13.0 48.6 5.6 12.6 59 MeO MeO Me 2 77-8 C H Q- S 48.8 5.7 13.0 49.7 5.7 14.6 60 MeO MeO Me 2 104-6 C H O S 50.0 5.6 14.9 49.7 5.6 15.2 61 MeO MeO Me 2 84-5 C H O4S 50.0 5.6 14.9 49.8 5.5 15.1 62 Meo MeO Me 2 -5 C H O S 50.0 5.6 14.9 49.9 5.6 15.0 63 C1 C1 Me 2 108-110 C,H C1 O S 37.4 2.8 14.3 37.6 2.9 14.0 64 C1 Me Me 2 100-2 C H Cl O S 47.0 4.4 15.7 46.7 4.5 15.3 65 Me Me Me 2 68 C H O S 58.7 6.6 17.4 58.6 6.5 17.2 The compound of Example 24 had b.p. -8C/1 mm.

The invention is further illustrated by the following examples of compositions in which all parts are by weight.

EXAMPLE I EXAMPLE II A mixture of 1 part of 3,4-dimethoxyphenylmethyl sulphoxide, and 9 parts of a tablet base comprising starch with the addition of 1 percent magnesium stearate was compressed into tablets.

Conveniently the tablets are of such a size as to contain 10 or 25mg of 3,4-dimethoxyphenylmethyl sulphoxide. Similarly tablets containing 50mg of 3,4-dimethoxyphenylmethyl sulphoxide were prepared from a mixture of 2 parts of the sulphoxide, 9 parts of starch together with 1 percent magnesium stearate.

EXAMPLE Ill Various strength capsules are prepared containing 3,4-dimethoxyphenylmethyl sulphoxide and the following ingredients (amounts are in mg):

The above ingredients may be screened through a 40 PS5. mesh screen before being mixed and filled into hard gelatine capsules.

EXAMPLES lV Ampoules were prepared containing mls of an isotenic solution prepared from 1 gm 3,4-dimethoxyphenylmethyl sulphoxide and 0.735 gm sodium chloride in 100 mls distilled water. The solution was stable to steam autoclaving at psi for 35 minutes.

EXAMPLE V The 3,4-dimethoxyphenylmethyl sulphoxide in each of the foregoing Examples I-IV may be replaced by 2,4-dimethoxyphenylmethyl sulphoxide, 3,4-dimethoxyphenylethyl sulphoxide, 2,S-dimethoxyphenylmethyl sulphoxide, 6-amino-3,4-dimethoxyphenylmethyl sulphone, 3,4-dimethoxyphenylmethyl sulphone, 2,5-dimethoxyphenylmethyl sulphone, 3,4-dimethoxyphenylpropyl sulphoxide, 3,5-dichlorophenylmethyl sulphoxide, 3,4,6-trimethoxyphenylmethyl sulphoxide, 3,S-dimethoxyphenylmethyl sulphoxide, or 3,4-diethylphenylmethyl sulphoxide.

Screening for antihypertensive activity has been carried out employing known pharmacological tests such as those using normotensive, DOCA and renal hypertensive rats according to the method of Stanton H.C. and White J.B., Arch. Int. Pharmacodyn. Ther. 154, No. 2, 351 (1966) and Weeks J.R. and Jones J.A., Proc. Exper. Biol & Med. 104, No. 4, 646 (1960).

The following are some of the test results obtained with compounds of said formula. The compounds were administered intraperitoneally at a dose of IOOmg/kg to groups of DOCA hypertensive rats, and the figures are for the maximum percentage fall in the blood pressure.

The following are some of the results when compounds were administered orally to groups of DOCA hypertensive rats at dosage levels of 20,50 and 100 mg/kg. At each dose level a group of six rats was employed for each compound. The figures are for the maximum percentage fall in the blood pressure.

No. of Example. Fall in Blood Pressure 50 100 mg/kg dose 1 3O 36 53 2 21 34 50 4 5 14 21 5 33 41 50 8 16 28 42 l4 l8 18 26 24 25 44 It is expected that the likely human oral dose of a composition of the invention will be 200-500 mg of active ingredient per day for the relief of hypertension.

It has been shown that these compounds possess interesting and prolonged vasodilator actions which are exerted on the smooth muscle fibres of the blood vessels of the peripheral circulation. There is no action on the autonomic nervous system. That the vasodilator activity is of peripheral origin is demonstrated by the following findings:

1. The compounds have hypotensive activity in spinalised cats and pithed rats.

2. The compounds are active against vasocenstriction produced by noradrenaline and vasopressin in a variety of isolated perfused blood vessel preparation e.g. rabbit ear, rat mesenteric vessels.

Further the compounds an'tagonise the pressor effects of noradrenaline, tyramine and angiotensin in the anaesthetised cat and dog at 3 to 10 mg/kg. Nictitating membrane contractions were also antagonised.

We claim:

1. A method for treating hypertension which comprises administering to humans an antihypertensive effective amount of a compound of the formula 0 (R; ll

wherein R is alkoxy of l to 3 carbon atoms; R is H, or alkyl or alkoxy of l to 3 carbon atoms and R is alkyl of 1 to 7 carbon atoms, alkenyl or alkynyl of 3 to 5 carbon atoms orhydroxyalkyl of 2 to 3 carbon atoms.

2. A method as claimed in claim 1 wherein the compound is 3,4dimethoxyphenylmethyl sulphoxide.

3. A method=as claimed in claim 1 wherein the compound is 3,4-dimethoxyphenylpropyl sulphoxide.

4. A method as claimed in claim 1 wherein the compound is 3,S-dimethoxyphenylmethyl sulphoxide.

5. A method as'claimed in claim 1 wherein the compound is 3,4,6-trimethoxyphenylmethyl sulphoxide.

6. The method of claim 1 wherein the compound is 2-methyl-4,5-dimethoxyphenylmethyl sulphoxide.

7. A pharmaceutical composition for the treatment of hypertension which comprises an antihypertensive effective amount of a compound of the formula wherein R is alkoxy of l to 3 carbon atoms; R is H, or alkyl or alkoxy of l to 3 carbon atoms and R is alkyl of l to 7 carbon atoms, alkenyl or alkynyl of 3 to 5 carbon atoms or hydroxyalkyl of 2 to 3 carbon atoms; together with a pharmaceuticallly acceptable diluent or carrier.

8. A pharmaceutical composition as claimed in claim 7 in unit dosage form for oral administration comprising from 10 to mg of said compound.

9. A pharamceutical composition as claimed in claim 10. The composition of claim 7 wherein the com- 7 in unit dosage form for parenteral administration pound is 2-methyl-4,S-dimethoxyphenylmethyl sulphcomprising from 1 to mg of said compound per 1 mi oxide.

of the composition. 

1. A METHOD FOR TREATING HYPERTENSION WHICH COMPRISES ADMINISTERING TO HUMANS AN ANTIHYPERTENSIVE EFFECTIVE AMOUNT OF A COMPOUND OF THE FORMULA
 2. A method as claimed in claim 1 wherein the compound is 3,4-dimethoxyphenylmethyl sulphoxide.
 3. A method as claimed in claim 1 wherein the compound is 3,4-dimethoxyphenylpropyl sulphoxide.
 4. A method as claimed in claim 1 wherein the compound is 3,5-dimethoxyphenylmethyl sulphoxide.
 5. A method as claimed in claim 1 wherein the compound is 3,4,6-trimethoxyphenylmethyl sulphoxide.
 6. The method of claim 1 wherein the compound is 2-methyl-4,5-dimethoxyphenylmethyl sulphoxide.
 7. A pharmaceutical composition for the treatment of hypertension which comprises an antihypertensive effective amount of a compound of the formula
 8. A pharmaceutical composition as claimed in claim 7 in unit dosage form for oral administration comprising from 10 to 100 mg of said compound.
 9. A pharamceutical composition as claimed in claim 7 in unit dosage form for parenteral administration comprising from 1 to 10 mg of said compound per 1 ml of the composition.
 10. The composition of claim 7 wherein the compound is 2-methyl-4,5-dimethoxyphenylmethyl sulphoxide. 